should I use old well or drill new one

I bought 14 acres and am in the process of building a house. there is an old drilled well, about 400' with pump at 240'. This well is less than 100' from where two chicken houses used to be, from 65' till 05'. Also there are 4 bury pits on property where chemicals where added to help dispose of dead birds. The closest one to well is about 100' and was used up until about 90'. I don't know if county/university tests would show anything as they would have to test for specifics, right?? The most recent bury pit was used up until 05' and is about 150' from well. Should I use this well or drill elsewhere?

Also, we have lots of iron in water around here. I have been told a shallower well (about 60-80') has less iron than a deeper well??

so you would trust water at 60-80' on your property over water from 400'? i would also think that the shallower well would have more iron than one at 400, at least thats the way it works where i am in NE FL. a well deeper than about 250 in my area will have 0 iron.

i live on an old chicken farm started in the late 50's. For the first 21 years of my life, our house was fed by the oldest well on the farm that is about 30' from a chicken house. now i drink water from the 2nd oldest well on the farm thats across the street, right beside the hatchery (where the real chemicals are). lol, i think you will probably live.

If I had a new well drilled or bored at 60'-80'. I would do so as far away from chicken houses, pits, as I could. I don't know what depth water to trust, I am obviously confused and going by what I've been told by a well driller and my neighbor (who has had both type wells) and what they say about about iron in water at different depths.

So we know you can apparently get water from 80' and 400 where u live. I wonder why one would pay per foot an extra 320' if the water at 80' was "better". Chicken farmers are cheap, I know they wouldn't have paid more to go deeper for worse water. The driller i understand, he wants money. I try to sell a well when someone calls me too. I would get some more opinions before I spent several thousand dollars on a well and pump system with water that is likely to be of less quality than what you already own (all because of a confused neighbor). There is no question I would use the current well on the property, but that's just me.

It is my understanding that the 80' well would run out for the chicken houses as they use alot of water during the summer and have to mist all day, while for household use it was sufficent (the neighbors dad had the chicken houses) Thanks for your help and any other replies are appreciated...

So like justwater says, the 80' well doesn't make as much water. No matter the depth of the well, one of the most important things is how good the well was sealed with concrete or grout. It doesn't matter how far away the well is, when it rains and washes stuff right up to your well head. I would just test the water for several things. it would help to know what those chemicals they used were.